Normally, when a plurality of programs or applications on a single computer need to use the bus at the same time, each program is granted less BW (Bandwidth) than it would prefer to use.
In many computers, the OS (Operating System) can be instructed to give priority to some programs and require others to operate in the background. However, if too many of the priority programs require access to the bus, one or more of the priority programs will have to operate at a less than desirable speed. Although such a slowdown situation may be tolerable for some programs, such as word processors, they may be completely unacceptable in a situation where a game, video or other high bandwidth program is being utilized. Inadequate bandwidth, in such a situation, may result in a distorted display, stilted motion or some other similar, and less than desirable, end result.
When the environment is more complex and a plurality of processors and other intelligent entities or devices must access the same bus, the BW (Bandwidth) problem is compounded. Further, when a plurality of PUs are interconnected, programs may be written such that more than one PU is utilized in completing program results. In such a situation, the different parts of the program are likely to attempt communication with a common resource using a common path to get to that resource. Therefore parts of a program may be fighting each other to obtain sufficient BW to complete the program.
It would be desirable to find a method of controlling or governing access to the bus whereby high priority programs are assured of having the BW they need to operate properly. It would further be desirable to be able to guarantee a minimum BW to managed devices, programs or applications and still allow a class of managed device(s) additional BW in situations where the resource is not being heavily used. If would further be desirable to be able to apply the given BW to a managed entity regardless of the PU that is being used to operate or complete the program.